JP2012251496A - Flow rate control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flow rate control valve which can effectively prevent the inclination of a valve body over the whole area of a moving range of the valve body.SOLUTION: A PCV valve 40 comprises: a case 42 having a gas passage 55; the valve body 60 arranged in the gas passage 55 so as to advance and retreat; and a spring 72 which energizes the valve body 60 to the retreating direction. A measurement part 70 is formed of a measurement hole 58 formed at the gas passage 55 and a measurement face 62 formed at the valve body 60. An upstream-side passage wall face 47 and a downstream-side passage wall face 49 of the gas passage 55 are formed into hollow cylindrical shapes. At the valve body 60, there are arranged a first guide flange 65 which is slidably connected to the upstream-side passage wall face 47 and has an opening hole 66, and a second guide flange 67 which is slidably connected to the downstream-side passage wall face 49 and has an opening hole 68.

Description

  The present invention relates to a flow control valve that controls the flow rate of a fluid.

  For example, a PCV (Positive Crankcase Ventilation) valve is used as a flow control valve for controlling the flow rate of blow-by gas in a blow-by gas reduction device for an internal combustion engine (engine) in a vehicle such as an automobile (see, for example, Patent Document 1).

A conventional example of a PCV valve will be described. FIG. 13 is a cross-sectional view showing a PCV valve.
As shown in FIG. 13, the PCV valve 1 includes a case 2, a valve body 3, and a spring 4. The case 2 is provided with a gas passage 5 extending in the axial direction (left-right direction in FIG. 13). Blow-by gas flows through the gas passage 5. The valve body 3 is provided in the gas passage 5 so as to be able to advance and retract in the axial direction. Further, the spring 4 is interposed between the case 2 and the valve body 3 and urges the valve body 3 in the backward direction (rightward in FIG. 13). A measuring hole 6 a is formed in the middle of the gas passage 5. The valve body 3 has a measuring surface 6b. The measuring part 6 is constituted by the measuring hole 6a and the measuring surface 6b.

  The PCV valve 1 controls, or measures, the flow rate of the blow-by gas flowing through the gas passage 5 by adjusting the passage cross-sectional area of the metering unit 6 by moving the valve body 3 back and forth. Further, the passage wall surface 5a on the upstream side of the measuring portion 6 of the gas passage 5 in the case 2 and the passage wall surface 5b on the downstream side of the measuring portion 6 are each formed in a hollow cylindrical shape. Further, an annular plate-shaped guide flange 7 is formed at the rear end portion (the right end portion in FIG. 13) of the valve body 3 so as to project outward in the radial direction. The guide flange 7 (specifically, the outer peripheral surface) is slidably contactable with the passage wall surface 5 a on the upstream side of the gas passage 5. A notch 7 a that allows the passage of blow-by gas is formed on the outer periphery of the guide flange 7. A plurality of (for example, three) guide ribs 8 extending in a straight line in the axial direction of the valve body 3 are radially formed at the front portion of the valve body 3. The guide rib 8 (specifically, the outer end surface) can be in sliding contact with the passage wall surface 5 b on the downstream side of the gas passage 5. Therefore, when the valve body 3 is advanced and retracted, the guide flange 7 is in sliding contact with the passage wall surface 5a on the upstream side of the case 2 and the guide rib 8 is in sliding contact with the passage wall surface 5b on the downstream side. Guided in the direction.

JP 2007-120660 A

  According to the PCV valve 1, as the valve body 3 moves forward from the retracted position (moves to the left in FIG. 13), the passage wall surface 5a on the upstream side with respect to the support portion of the guide rib 8 with respect to the wall surface 5b on the downstream side. The supporting portion of the guide flange 7 with respect to is approaching. That is, the distance between the support portion by the guide flange 7 and the support portion by the guide rib 8 with respect to the case 2 is narrowed. For this reason, there is a problem that the inclination of the valve body 3 is likely to increase as the valve body 3 moves forward. This makes it easy for the valve body 3 to rattle against the case 2, thereby causing abnormal noise such as a hitting sound due to rattling and a decrease in durability.

  The problem to be solved by the present invention is to provide a flow control valve capable of effectively preventing the inclination of the valve body over the entire movement range of the valve body.

The above-mentioned problem can be solved by a flow rate control valve having the gist of the configuration described in the claims.
According to the flow control valve recited in claim 1, a case in which a fluid passage is provided, a valve body provided in the fluid passage so as to be capable of moving forward and backward in an axial direction, and a spring that biases the valve body in a backward direction. A metering portion is formed by a metering hole formed in the middle of the fluid passage and a metering surface formed in the valve body, and flows through the fluid passage by adjusting the cross-sectional area of the metering portion by the advancement and retreat of the valve body A flow rate control valve for controlling the flow rate of fluid, wherein a passage wall surface upstream of the metering portion of the fluid passage and a passage wall surface downstream of the metering portion are each formed in a hollow cylindrical shape, Is provided with a flange-shaped first guide portion having an opening through which fluid flows and which is in sliding contact with the upstream passage wall surface, and the valve body is in sliding contact with the downstream passage wall surface and fluid A flange-shaped second guide portion having an opening for circulation is provided. It is. According to this configuration, when the valve body is advanced and retracted, the first guide portion is in sliding contact with the passage wall surface on the upstream side of the case, and the second guide portion is in sliding contact with the passage wall surface on the downstream side. Guided in the axial direction. Thereby, the operational stability of the valve body can be improved. Further, the distance between the support portion by the first guide portion and the support portion by the second guide portion with respect to the case is constant and does not change over the entire movement range of the valve body. Therefore, the inclination of the valve body can be effectively prevented over the entire movement range of the valve body. As a result, rattling of the valve body with respect to the case can be suppressed, and generation of abnormal noise such as hitting sound due to rattling and deterioration of durability can be prevented.

  According to the flow control valve recited in claim 2, at least one guide portion of the first guide portion and the second guide portion is separated from the valve body, and the valve body provided in the fluid passage of the case The guide portion is attached. According to this configuration, the outer diameter of at least one guide portion of the first guide portion and the second guide portion and the inner diameter of the passage portion 59 corresponding to the guide portion are set to the hole diameter (inner diameter of the measuring portion). ) Can be set larger than. For this reason, a large flow rate fluid can be flowed.

  According to the flow control valve of the third aspect, the second guide portion is configured to be seated on the edge portion of the measuring hole when the valve body is retracted. According to this configuration, when the valve body is retracted (last retracted position), the second guide portion is seated with the hole edge portion of the measuring hole as the valve seat. As a result, the metering hole is closed, so that backflow of fluid can be prevented.

  According to the flow control valve described in claim 4, the first guide portion and the second guide portion are formed integrally with the valve body. According to this structure, the number of parts of a valve body and assembly man-hours can be reduced.

  According to the flow control valve recited in claim 5, the opening of at least one of the first guide part and the second guide part is concentrically connected to both end surfaces of the guide part and communicates with each other. A plurality of inflow-side opening holes and outflow-side opening holes, each having an arc shape; an inflow-side rib extending in a radial direction between the inflow-side opening holes in the guide portion; The ribs on the outflow side extending in the radial direction between the opening holes are arranged at positions shifted in the circumferential direction. According to this configuration, while reducing the radial strength of the guide portion by the inflow side rib and the outflow side rib, it is possible to suppress a decrease in the passage cross-sectional area of the opening due to the inflow side rib and the outflow side rib, The flow resistance of the fluid can be reduced. For this reason, a large flow rate fluid can be flowed.

  According to the flow control valve described in claim 6, it is a PCV valve used in a blow-by gas reduction device for an internal combustion engine. According to this configuration, the inclination of the valve body can be effectively prevented over the entire movement range of the valve body in the PCV valve.

It is sectional drawing which shows the PCV valve | bulb concerning Embodiment 1. FIG. It is the II-II sectional view taken on the line of FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 1. It is a block diagram which shows a blow-by gas reduction apparatus. It is sectional drawing which shows the PCV valve | bulb concerning Embodiment 2. FIG. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. It is sectional drawing which shows the peripheral part of a 2nd guide flange. It is sectional drawing which shows the peripheral part of the 2nd guide flange concerning Embodiment 3. FIG. It is sectional drawing which shows the PCV valve | bulb concerning Embodiment 4. FIG. 10 is a cross-sectional view taken along line X-X in FIG. 9. FIG. 10 is a sectional view taken along line XI-XI in FIG. 9. FIG. 10 is a cross-sectional view taken along line XII-XII in FIG. 9. It is sectional drawing which shows the PCV valve | bulb concerning a prior art example.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

[Embodiment 1]
The first embodiment will be described. In Embodiment 1, the PCV valve used for the blow-by gas reduction apparatus of an internal combustion engine is illustrated as a flow control valve. For convenience of explanation, the PCV valve will be explained after explaining an example of the blow-by gas reducing device. FIG. 4 is a block diagram showing the blow-by gas reduction device.
As shown in FIG. 4, the blow-by gas reduction device 10 introduces blow-by gas that has leaked into the crankcase 15 of the cylinder block 14 from the combustion chamber of the engine body 13 of the engine 12 that is an internal combustion engine into the intake manifold 20. This is a system for burning again in the combustion chamber.

  The engine body 13 includes the cylinder block 14, an oil pan 16 fastened to the lower surface side of the crankcase 15, a cylinder head 17 fastened to the upper surface side of the cylinder block 14, and an upper surface side of the cylinder head 17. The cylinder head cover 18 is fastened. The engine body 13 obtains driving force through a process such as intake, compression, explosion, and exhaust. Further, blow-by gas is generated in the engine main body 13, that is, in the crankcase 15 and in the cylinder head cover 18 communicating with the crankcase 15 as combustion occurs in the combustion chamber (not shown) of the engine main body 13. . Further, the inside of the cylinder head cover 18 and the inside of the crankcase 15 into which blow-by gas flows corresponds to “inside of the engine body” in this specification.

  The cylinder head cover 18 is provided with a fresh air inlet 18a and a blow-by gas outlet 18b. One end (downstream end) of the fresh air introduction passage 30 communicates with the fresh air introduction port 18a. One end (upstream end) of the blowby gas passage 36 is communicated with the blowby gas outlet 18b. The fresh air inlet 18 a and / or the blow-by gas outlet 18 b can be provided in the crankcase 15 instead of the cylinder head cover 18.

  One end (downstream end) of the intake manifold 20 is communicated with the cylinder head 17. The intake manifold 20 includes a surge tank 21. An air cleaner 25 communicates with the other end (upstream end) of the intake manifold 20 via a throttle body 24 and an intake pipe 23. The throttle body 24 includes a throttle valve 24a. The throttle valve 24a is connected to, for example, an accelerator pedal (not shown), and is opened and closed according to the depression amount (operation amount) of the pedal. The air cleaner 25 introduces air so-called fresh air, and has a built-in filter element 26 for filtering the fresh air. The air cleaner 25, the intake pipe 23, the throttle body 24, and the intake manifold 20 form a series of intake passages 27 for introducing fresh air, that is, intake air into the combustion chamber of the engine body 13. In the intake passage 27, a passage portion upstream of the throttle valve 24a is referred to as an upstream intake passage portion 27a, and a passage portion downstream of the throttle valve 24a is referred to as a downstream intake passage portion 27b.

  A fresh air inlet 29 is formed in the intake pipe 23. The fresh air inlet 29 communicates with the other end (upstream end) of the fresh air introduction passage 30. The fresh air introduction passage 30 is provided with a backflow prevention valve 32. The backflow prevention valve 32 allows the flow of so-called fresh air (see arrow Y1 in FIG. 4) from the intake passage portion 27a on the upstream side into the crankcase 15 and flows in the reverse direction, that is, backflow. (See arrow Y3 in FIG. 4). The surge tank 21 has a blow-by gas inlet 34 formed therein. The blow-by gas introduction port 34 communicates with the other end (downstream end) of the blow-by gas passage 36.

  Next, the operation of the blowby gas reduction device 10 will be described. When the engine 12 is light and medium load, the throttle valve 24a is almost fully closed. For this reason, a negative pressure (a negative pressure that increases toward the vacuum side) greater than that of the upstream intake passage portion 27a is generated in the intake passage portion 27b on the downstream side of the intake passage 27. Therefore, the blow-by gas in the engine body 13 is introduced into the intake passage portion 27b on the downstream side through the blow-by gas passage 36 (see arrow Y2 in FIG. 4). At this time, the flow rate of blow-by gas flowing through the blow-by gas passage 36 is controlled by a PCV valve 40 (described later).

  Further, as the blow-by gas is introduced into the intake passage portion 27b on the downstream side from the engine body 13 through the blow-by gas passage 36, the backflow prevention valve 32 is opened. As a result, fresh air in the intake passage portion 27a upstream of the intake passage 27 is introduced into the engine body 13 through the fresh air introduction passage 30 (see arrow Y1 in FIG. 4). Then, the fresh air introduced into the engine body 13 is introduced into the downstream intake passage portion 27b through the blow-by gas passage 36 together with the blow-by gas (see arrow Y2 in FIG. 4). As described above, the inside of the engine body 13 is scavenged.

  Further, when the engine 12 is at a high load, the opening degree of the throttle valve 24a becomes large. Therefore, the pressure in the intake passage portion 27b on the downstream side of the intake passage 27 approaches the atmospheric pressure. Therefore, the blow-by gas in the engine main body 13 becomes difficult to be introduced into the intake passage portion 27b on the downstream side, and the pressure in the engine main body 13 also approaches atmospheric pressure. For this reason, the flow rate of fresh air introduced into the engine body 13 from the upstream intake passage portion 27a through the fresh air introduction passage 30 is also reduced. Further, by closing the backflow prevention valve 32, the backflow of blowby gas from the engine body 13 to the fresh air introduction passage 30 (see arrow Y3 in FIG. 4) is prevented.

  The blow-by gas passage 36 is provided with a PCV valve 40 as a flow rate control valve for controlling the flow rate of blow-by gas. The PCV valve 40 controls or measures the flow rate of the blowby gas in accordance with the differential pressure between the upstream pressure and the downstream pressure of the blowby gas, thereby preventing a sudden change in the flow rate of the blowby gas due to a sudden change in the differential pressure.

Next, the PCV valve 40 will be described. 1 is a sectional view showing a PCV valve, FIG. 2 is a sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a sectional view taken along the line III-III in FIG. For convenience of explanation, the left side of FIG. 1 is the front side, and the right side is the rear side.
As shown in FIG. 1, the case 42 of the PCV valve 40 is made of, for example, resin and has a hollow cylindrical shape. The hollow portion of the case 42 is a gas passage 55 extending in the axial direction (left and right direction in FIG. 1). Further, the rear end portion (right end portion in FIG. 1) of the case 42 is connected to a passage portion on the upstream side of the blow-by gas passage 36 (see FIG. 4). Further, the front end portion (left end portion in FIG. 1) of the case 42 is connected to a passage portion on the downstream side of the blow-by gas passage 36. The rear end of the case 42 may be connected to the blow-by gas outlet 18b (see FIG. 4) of the cylinder head cover 18. A blow-by gas that is a fluid flows in the gas passage 55. The gas passage 55 corresponds to a “fluid passage” in this specification.

  In the middle of the gas passage 55 of the case 42, a stepped surface 43 having a small diameter on the front side and a large diameter on the rear side is formed. On the upstream side of the stepped surface 43 of the case 42, that is, on the gas inflow side (right side in FIG. 1), a hollow cylindrical upstream side wall surface 47 is formed. The inside of the upstream passage wall surface 47 is an upstream passage portion 57. Further, on the downstream side of the stepped surface 43 of the case 42, that is, on the gas outflow side (left side in FIG. 1), a hollow cylindrical downstream wall surface 49 is formed. The inside of the passage wall surface 49 on the downstream side is a passage portion 59 on the downstream side. Further, the upstream end (the right side in FIG. 1) of the downstream passage portion 59 is set to the measuring hole 58. Accordingly, the upstream end portion of the downstream passage wall surface 49 is a hole wall surface 48 of the measuring hole 58.

  In the case 42, that is, in the gas passage 55, a valve body 60 is disposed so as to be able to advance and retract in the axial direction (left and right direction in FIG. 1). The valve body 60 is made of, for example, a resin and mainly includes a valve main body 61 formed in a substantially cylindrical shape. On the outer peripheral surface of the valve body 61, a tapered taper measuring surface 62 is formed concentrically. A tapered taper shaft portion 63 projects concentrically at the distal end portion (front end portion) of the valve main body portion 61.

  A first guide flange 65 is formed concentrically at the rear end portion (right end portion in FIG. 1) of the valve main body portion 61 so as to project radially outward. The first guide flange 65 (specifically, the outer peripheral surface) is capable of sliding contact with the passage wall surface 47 on the upstream side of the case 42 (see FIG. 2). The first guide flange 65 is formed with a plurality (four in FIG. 2) of opening holes 66 that allow the passage of blow-by gas. The opening holes 66 have an arc shape concentric with the first guide flange 65 and are arranged at equal intervals in the circumferential direction. The first guide flange 65 corresponds to a “first guide portion” in this specification. The opening hole 66 corresponds to an “opening” in the present specification. Further, it is sufficient that at least one opening hole 66 is formed in the first guide flange 65. The opening hole 66 is not limited to an arc shape, and can be changed to an appropriate shape. Further, the opening portion of the first guide flange 65 can be formed by a notch surface, a concave groove, or the like that opens in the outer peripheral portion of the first guide flange 65 instead of the opening hole 66.

  A second guide flange 67 is formed concentrically at the front end portion (left end portion in FIG. 1) of the tapered shaft portion 63 of the valve main body portion 61 so as to project radially outward. The second guide flange 67 (specifically, the outer peripheral surface) is capable of sliding contact with the passage wall surface 49 on the downstream side of the case 42 (see FIG. 3). The second guide flange 67 is formed with a plurality of (three shown in FIG. 2) opening holes 68 that allow the passage of blow-by gas. The opening holes 68 have an arc shape concentric with the second guide flange 67 and are arranged at equal intervals in the circumferential direction. The plate thickness (axial thickness) of the second guide flange 67 is set to be the same as or substantially the same as the plate thickness (axial thickness) of the first guide flange 65. The second guide flange 67 corresponds to a “second guide portion” in the present specification. The opening hole 68 corresponds to an “opening” in the present specification. The second guide flange 67 only needs to have at least one opening hole 68 formed therein. The opening hole 68 is not limited to an arc shape, and can be changed to an appropriate shape. Further, the opening of the second guide flange 67 can be formed by a notch, a concave groove or the like that opens in the outer peripheral portion of the second guide flange 67 instead of the opening hole 68. The plate thickness (axial thickness) of the second guide flange 67 may be thicker or thinner than the plate thickness (axial thickness) of the first guide flange 65.

  In the valve body 60, the first guide flange 65 and the second guide flange 67 are formed by integral molding together with the valve body 61. The first guide flange 65 and / or the second guide flange 67 may be formed separately from the valve body 61 and the flange may be attached to the valve body 61.

  The valve body 60 is inserted from the upstream passage portion 57 of the gas passage 55 into the downstream passage portion 59 through the measuring hole 58 (see FIG. 1). Accordingly, the first guide flange 65 is supported on the passage wall surface 47 on the upstream side of the case 42 so as to be slidable (see FIG. 2). Further, the second guide flange 67 is supported by the passage wall surface 49 on the downstream side of the case 42 so as to be slidable (see FIG. 3). Therefore, when the valve body 60 is advanced or retracted, the guide body 65 is guided in the axial direction with the guide flanges 65 and 67 on both sides of the valve body 60 supported by the case 42, so that the inclination of the valve body 60 is suppressed. In the present embodiment, an appropriate number of shallow concave portions 47a (four are shown in FIG. 2) extending in the axial direction are formed on the passage wall surface 47 on the upstream side at equal intervals in the circumferential direction. . Further, the recessed portion 47a may be formed in the passage wall surface 49 on the downstream side. Moreover, the number of the recessed parts 47a can be increased / decreased suitably. Further, the concave portion 47a may be omitted.

  As shown in FIG. 1, a measuring portion 70 is configured by a measuring hole 58 (specifically, a hole wall surface 48) of the case 42 and a measuring surface 62 of the valve main body 61. Therefore, as the valve body 60 moves backward (moves to the right in FIG. 1), the effective opening area of the measuring portion 70, that is, the passage cross-sectional area is increased. Conversely, as the valve body 60 moves forward (moves to the left in FIG. 1), the passage cross-sectional area of the measuring portion 70 is reduced. The valve body 60 corresponds to the “valve body” in this specification.

  A spring 72 made of a compression coil spring is interposed between the case 42 and the valve body 60. The spring 72 is fitted to the valve main body 61 of the valve body 60. The rear end portion of the spring 72 is locked to the first guide flange 65. Further, the front end portion of the spring 72 is locked to the stepped surface 43 of the case 42. The spring 72 always urges the valve body 60 in the backward direction (rightward in FIG. 1). The inner diameter of the front end 47b (see FIG. 1) of the upstream passage wall surface 47 is narrowed so as to be slightly larger than the outer diameter of the spring 72.

  An annular plate-like end plate 44 is attached to the rear end portion (right end portion in FIG. 1) of the case 42 by welding, bonding, or the like. The hollow hole portion of the end plate 44 is an inlet 56 of the gas passage 55. Further, when the valve body 60 is retracted (last retracted position), the first guide flange 65 is seated with the end plate 44 as the valve seat.

  Next, the operation of the PCV valve 40 will be described. When the passage portion 59 on the downstream side of the passage portion 57 on the upstream side of the gas passage 55 in the case 42 becomes a low pressure (negative pressure), the blow-by gas flows into the passage portion 57 on the upstream side from the inlet 56, It flows out through the measurement hole 58 and the passage portion 59 on the downstream side. At this time, the blow-by gas flows through the opening hole 66 of the first guide flange 65 of the valve body 60 and the opening hole 68 of the second guide flange 67 of the valve body 60. Further, when blow-by gas flows through the gas passage 55, it corresponds to the differential pressure between the upstream pressure of the upstream passage portion 57 and the downstream pressure of the downstream passage portion 59 (including the biasing force of the spring 72). The valve body 60 advances and retreats (moves in the axial direction). Thereby, the flow rate of the blow-by gas flowing through the gas passage 55 is controlled, that is, measured. Specifically, when the upstream pressure is greater than the downstream pressure and the differential pressure between the upstream pressure and the downstream pressure is large, the valve body 60 is advanced against the biasing force of the spring 72. Thereby, since the passage cross-sectional area of the metering unit 70 is reduced, the flow rate of blow-by gas is reduced. Further, when the differential pressure between the upstream pressure and the downstream pressure becomes small, the valve body 60 is retracted by the urging force of the spring 72. Thereby, since the passage cross-sectional area of the metering unit 70 is increased, the flow rate of blow-by gas is increased. In this way, the flow rate of the blow-by gas flowing through the gas passage 55 is controlled by increasing or decreasing the passage cross-sectional area of the measuring unit 70. Further, the first guide flange 65 is seated on the end plate 44 when the valve body 60 is retracted (last retracted position). As a result, the opening hole 66 of the first guide flange 65 is closed by the end plate 44 and the gas passage 55 is blocked, so that backflow of blow-by gas such as backfire can be prevented.

  According to the PCV valve 40 described above, when the valve body 60 is advanced and retracted, the first guide flange 65 is in sliding contact with the passage wall surface 47 on the upstream side of the case 42 and the second guide flange 67 is slid on the passage wall surface 49 on the downstream side. By the dynamic contact, the valve body 60 is guided in the axial direction (see FIGS. 1 to 3). Thereby, the operational stability of the valve body 60 can be improved. Further, the distance between the support portion by the first guide flange 65 and the support portion by the second guide flange 67 with respect to the case 42 is constant over the entire moving range of the valve body 60. Therefore, the inclination of the valve body 60 can be effectively prevented over the entire movement range of the valve body 60. As a result, rattling of the valve body 60 with respect to the case 42 can be suppressed, and generation of abnormal noise such as hitting sound due to rattling and deterioration of durability can be prevented.

  A first guide flange 65 and a second guide flange 67 are formed on the valve body 60 by integral molding. For this reason, the number of parts and assembly man-hours of the valve body 60 can be reduced.

[Embodiment 2]
Embodiment 2 will be described. Since this embodiment and subsequent embodiments are obtained by changing a part of the first embodiment, the changed portion will be described and redundant description will be omitted. 5 is a cross-sectional view showing the PCV valve, FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 is a cross-sectional view showing the periphery of the second guide flange.
As shown in FIG. 5, in this embodiment, the end plate 44 is omitted from the case 42 in the PCV valve 40 of the first embodiment (see FIG. 1). Further, the inner diameter of the passage wall surface 49 on the downstream side is larger than the inner diameter of the hole wall surface 48 of the measuring hole 58. In the present embodiment, the inner diameter of the downstream passage wall surface 49 is set to be the same as the inner diameter of the upstream passage wall surface 47. An annular protruding wall having a stepped surface 43 and a hole wall surface 49 of the measuring hole 58 between the upstream side wall surface 47 and the downstream side wall surface 49 and projecting radially inward. 45 is formed. On the downstream side of the overhanging wall 45 (left side in FIG. 5), a stepped surface 46 having a large diameter on the front side and a small diameter on the rear side is formed (see FIG. 7). The overhanging wall 45 corresponds to the “hole edge of the measuring hole” in this specification.

  As shown in FIG. 7, the second guide flange (reference numeral 74) of the valve body 60 is formed separately from the valve main body 61. Instead of the tapered shaft portion 63 (see FIG. 1), a support shaft portion 77 is formed concentrically at the distal end portion (front end portion) of the valve body portion 61 of the valve body 60. Prior to the attachment of the second guide flange 74, the valve body 61 having the first guide flange 65 is inserted into the downstream passage portion 59 from the upstream passage portion 57 in the gas passage 55 through the measuring hole 58. Is inserted (see FIG. 5).

  The second guide flange 74 is formed in an annular plate shape having mounting holes 74a concentrically (see FIGS. 6 and 7). Further, an opening hole 68 is formed in the second guide flange 74 similarly to the second guide flange 67 (see FIG. 3). Further, a groove portion 69 is formed on the rear end surface (the right end surface in FIG. 7) of the second guide flange 74 so as to be continuous with both the opening holes 66 adjacent in the circumferential direction (see FIG. 6). The groove 69 is effective for reducing the weight of the second guide flange 74. The second guide flange 74 corresponds to a “second guide portion” in this specification. Further, the groove 69 may be formed on the front end face (left end face in FIG. 5) of the second guide flange 74. Further, similarly to the second guide flange 74, the groove portion 69 may be formed on the rear end surface and / or the front end surface of the first guide flange 65.

  The second guide flange 74 is attached in a state in which the attachment hole 74a is fitted to the support shaft portion 77 of the valve main body portion 61 disposed in the case 42 (see FIG. 7). As a means for attaching the second guide flange 74 to the support shaft portion 77, for example, means such as welding, press fitting, and caulking can be used.

  On the rear end surface (the right end surface in FIG. 7) of the second guide flange 74, a tapered taper seal surface 79 is formed concentrically. The seal surface 79 is disposed between the opening hole 68 and the attachment hole 74a. Further, the seal surface 79 faces the overhanging wall 45 of the case 42. When the valve body 60 is retracted (last retracted position), the second guide flange 74 is seated with the overhanging wall 45 (specifically, the hole edge on the downstream side of the measuring hole 58) as the valve seat (in FIG. (See dotted line 79).

  According to the PCV valve 40 of the present embodiment, the second guide flange 74 is separated from the valve body 61 of the valve body 60, and the support shaft 77 of the valve body 60 provided in the gas passage 55 of the case 42 has its A second guide flange 74 is attached. Therefore, the outer diameter of the second guide flange 74 and the inner diameter of the downstream passage portion 59 can be set larger than the hole diameter (inner diameter) of the measuring hole 58 of the measuring portion 70. For this reason, a large flow rate of blow-by gas can be flowed. As a result, it can respond to the engine 12 with a large displacement. Instead of the second guide flange 74, the first guide flange 65 is separated from the valve body 61 of the valve body 60, and the first guide flange is attached to the valve body 60 provided in the gas passage 55 of the case 42. It is good also as a structure which attaches 65.

  Further, when the valve body 60 is retracted (last retracted position), the seal surface 79 of the second guide flange 74 is seated on the overhanging wall 45 (see a two-dot chain line 79 in FIG. 7). Accordingly, the metering hole 58 is closed and the gas passage 55 is blocked, so that the backflow of blow-by gas can be prevented. For this reason, the end plate 44 (refer FIG. 1) in the said Embodiment 1 is omissible. The sealing surface 79 in the second guide flange 74 can be omitted.

[Embodiment 3]
A third embodiment will be described. FIG. 8 is a cross-sectional view showing the periphery of the second guide flange.
As shown in FIG. 8, in the present embodiment, the tapered seal surface 79 (see FIG. 7) of the second guide flange 74 in the PCV valve 40 of the second embodiment (see FIG. 5) is a plane perpendicular to the axis. The seal surface (reference numeral 81) is changed. As in the second embodiment, the sealing surface 81 is seated with the overhanging wall 45 as a valve seat when the valve body 60 is retracted (see a two-dot chain line 81 in FIG. 8). At this time, the seal surface 81 comes into surface contact with the stepped surface 46 on the downstream side of the overhanging wall 45.

[Embodiment 4]
A fourth embodiment will be described. 9 is a cross-sectional view showing the PCV valve, FIG. 10 is a cross-sectional view taken along line XX in FIG. 9, FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. It is arrow sectional drawing.
As shown in FIG. 9, in this embodiment, the opening hole 68 (see FIGS. 6 and 7) of the second guide flange 74 in the PCV valve 40 of Embodiment 2 is changed to an opening (reference numeral 83). It is a thing.

  That is, a plurality (two are shown in FIG. 10) of opening holes 84 on the inflow side are formed on the end surface of the second guide flange 74 on the gas inflow side, that is, the rear end surface (the right end surface in FIG. 9). Yes. As shown in FIG. 10, the opening holes 84 on the inflow side are arc-shaped concentric with the second guide flange 74 and are arranged at equal intervals in the circumferential direction. In addition, the inflow side opening hole portion 84 is formed in a vertically symmetrical manner, and a radial direction is provided between the inner peripheral portion and the outer peripheral portion of the inflow side opening hole portion 84 of the second guide flange 74. Left and right inflow side ribs 85 are formed. A seal surface 79 is formed concentrically between the opening hole 68 and the mounting hole 74a in the rear end surface (right end surface in FIG. 7) of the second guide flange 74, as in the second embodiment. .

  A plurality (two are shown in FIG. 11) of outlet holes 87 on the outflow side are formed on the end surface on the gas outflow side of the second guide flange 74, that is, the front end surface (left end surface in FIG. 9). The outflow side opening hole 87 has the same shape as the inflow side opening hole 84. Further, as shown in FIG. 11, the opening holes 87 on the outflow side are arc-shaped concentric with the second guide flange 74 and are arranged at equal intervals in the circumferential direction. Further, the outflow side opening hole portion 87 is formed in a bilaterally symmetric shape, and a radial direction is provided between the inner peripheral portion and the outer peripheral portion of the outflow side opening hole portion 84 of the second guide flange 74. The upper and lower outflow side ribs 88 are formed. That is, the outflow side rib 88 is arranged at a position shifted by 90 ° in the circumferential direction with respect to the inflow side rib 85. The inflow side end portion (rear end portion) of the outflow side opening hole portion 87 and the outflow side end portion (front end portion) of the inflow side opening hole portion 84 communicate with each other. For this reason, in the communication part of both the opening hole parts 84 and 87, it is the annular hole part 89 continuous in the circumferential direction (refer FIG. 12). Accordingly, the opening 83 of the second guide flange 74 is constituted by the inflow side opening hole 84, the outflow side opening hole 87, and the annular hole 89.

  According to the present embodiment, while the radial strength of the second guide flange 74 is improved by the inflow side rib 85 and the outflow side rib 88, the opening 83 of the inflow side rib 85 and the outflow side rib 88 is improved. A reduction in passage cross-sectional area can be suppressed. That is, as shown in FIGS. 10 and 11, the passage cross-sectional area of the opening 83 decreases by an amount corresponding to the cross-sectional area of the two ribs 85 and 88 on the inflow side and the outflow side. This means that the amount of reduction in the passage cross-sectional area of each of the opening hole portions 84 and 87 is smaller than when the passage cross-sectional area of the opening 83 is reduced by an amount corresponding to the cross-sectional area of four ribs, for example. become. For this reason, the flow resistance of blow-by gas can be reduced and a large flow rate of blow-by gas can be flowed. As a result, it can respond to the engine 12 with a large displacement. Similar to the second guide flange 74, an opening 83 may be formed in the first guide flange 65 instead of the opening hole 66.

  The present invention is not limited to the above-described embodiment, and modifications can be made without departing from the gist of the present invention. For example, the present invention can be applied not only to the PCV valve 40 but also to a flow control valve that controls the flow rate of fluid other than blow-by gas.

10 ... Blow-by gas reduction device 12 ... Engine (internal combustion engine)
40 ... PCV valve (flow control valve)
42 ... Case 45 ... Overhang wall (hole edge of measuring hole)
47 ... Upstream passage wall surface 49 ... Downstream passage wall surface 55 ... Gas passage (fluid passage)
58 ... Measuring hole 60 ... Valve body (valve body)
62 ... Measuring surface 65 ... First guide flange (first guide part)
66 ... opening hole (opening)
67 ... Second guide flange 68 ... Opening hole (opening)
DESCRIPTION OF SYMBOLS 70 ... Measurement part 72 ... Spring 74 ... 2nd guide flange 83 ... Opening part 84 ... Inflow side opening hole part 85 ... Inflow side rib 87 ... Outflow side opening hole part 88 ... Outflow side rib

Claims (6)

A case with a fluid passage;
A valve body provided in the fluid passage so as to be capable of moving back and forth in the axial direction;
A spring for urging the valve body in the backward direction,
A measuring part is constituted by a measuring hole formed in the middle of the fluid passage and a measuring surface formed in the valve body,
A flow rate control valve for controlling a flow rate of a fluid flowing through a fluid passage by adjusting a passage cross-sectional area of the measuring portion by advancing and retracting the valve body;
The passage wall surface on the upstream side of the measuring portion of the fluid passage, and the passage wall surface on the downstream side of the measuring portion are each formed in a hollow cylindrical shape,
The valve body is provided with a flange-shaped first guide portion having an opening portion that is in sliding contact with the upstream passage wall surface and through which a fluid flows.
The flow rate control valve, wherein the valve body is provided with a flange-shaped second guide portion that has an opening portion that is in sliding contact with the downstream passage wall surface and through which fluid flows. The flow control valve according to claim 1,
At least one guide part of the first guide part and the second guide part is separated from the valve body, and the guide part is attached to the valve body provided in the fluid passage of the case. A flow control valve characterized by that. The flow control valve according to claim 2,
The flow rate control valve characterized in that the second guide portion is configured to be seated on a hole edge portion of the measuring hole when the valve body is retracted. The flow control valve according to claim 1,
The flow rate control valve, wherein the first guide portion and the second guide portion are integrally formed on the valve body. The flow control valve according to any one of claims 1 to 4,
The opening of at least one of the first guide part and the second guide part has a plurality of inflow side concentric and communicating with each other on both end surfaces of the guide part. It has an opening hole and an opening hole on the outflow side,
The inflow side ribs extending in the radial direction between the inflow side opening hole portions in the guide portion and the outflow side ribs extending in the radial direction between the outflow side opening hole portions are shifted in the circumferential direction. A flow control valve characterized by being placed in the position. A flow control valve according to any one of claims 1 to 5,
A flow control valve, which is a PCV valve used in a blow-by gas reduction device for an internal combustion engine.

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